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In this study. a novel near-infrared fluorescent-driven contrast agent (Ag-doped NaYF4:Yb3+/Er3+@NaYF4:Nd3+@NaGdF4) was synthesized using a coprecipitation-hydrothermal-solvothermal-solvothermal (CHSS) method. The results shows that hexagonal NaYF4:Yb3+/Er3+ with a diameter of 300 nm was successfully synthesized by the CHSS method. The new contrast agent was characterized using scanning electron microscopy, fluorescence spectrometry, transmission electron microscopy, energy-dispersive spectrometry and ultraviolet-visible light diffuse reflectance absorption spectroscopy. Even at low concentrations (0.2 M), this proposed contrast agent can be excited by near-infrared light with a wavelength of 980 nm and emits a dazzling green light with a wavelength of 540 nm, and the comparison of the luminescence intensity proves that doping with silver increases the luminescence intensity of the upconverted nanomaterial by nearly 13 times based on the calculated quantum yield. TEM images show the successful preparation of silver nanoparticles with a diameter of 30 nm, and the energy spectrum shows the successful doping of silver nanoparticles and the successful preparation of the core-shell structure of NaYF4:Yb3+/Er3+@NaYF4:Nd3+@NaGdF4. Furthermore, the mechanism of the increased luminous intensity has been studied using simulation calculations. Finally, cytotoxicity tests were used to test material which was modified by 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (DSPE-PEG2K), and the biocompatibility was significantly improved, meeting the standard for biological applications. [ABSTRACT FROM AUTHOR]

Two key concerns exist in contemporary cancer chemotherapy: limited therapeutic efficiency and substantial side effects in patients. In recent years, researchers have been investigating the revolutionary cancer treatment techniques of photodynamic therapy (PDT) and photothermal therapy (PTT) proposed by many scholars. A photothermal treatment of cancer was synthesized using the hydrothermal method which has high photothermal conversion efficiency and can generate reactive oxygen species (ROS) in cells. Photothermal treatment of tumors has a good short-term effect and photodynamic therapy lasts longer. However, both PTT and PDT have their inevitable shortcomings and it is difficult to completely eradicate a tumor using a single mode of treatment. PTT and PDT synergistic treatment not only inherits the advantages of low toxicity and side effects of phototherapy but also enables the two treatment methods to complement each other. It is an effective strategy to improve curative effects and reduce toxic and side effects. Furthermore, gold doped UCNPs have an exceptionally high target recognition for tumor cells. The gold doped UCNPs, in particular, are non-toxic to normal tissues, endowing the as-prepared medications with outstanding therapeutic efficacy and exceptionally low side effects. These findings may encourage the creation of fresh, effective imaging-guided approaches to meet the goal of photothermal cancer therapy. [ABSTRACT FROM AUTHOR]

Forest landscape multifunctionality (FLM) provides multiple benefits, such as climate regulation, water storage, and biodiversity maintenance. However, the external factors limiting FLM have not been fully identified, although addressing them could contribute to sustainable development. The present study aimed to identify and quantify the role of urbanization as an external factor that affects FLM. To this end, impervious area changes in Liaoyuan, China, were observed from 2000 to 2018, and 10 buffer zones at 500 m intervals were established outside the city. Within each buffer zone, we analyzed changes in forest landscape functions, including habitat maintenance, carbon sequestration, and water yield, as well as changes in the multifunctionality of their composition. The urbanization of Liaoyuan was significant in 2000–2018. The functions of the forest landscape became stronger and more stable as they were located further away from the urban edge. We refer to this pattern as the gradient effect of urbanization. Specifically, urbanization affected the investigated functions at a distance of 1000–2500 m. The FLM showed a more significant gradient effect of urbanization. The impact distance of urbanization on the FLM increased from 3000 m in 2000 to over 5000 m in 2018. This impact distance increased significantly whenever urbanization strengthened significantly (i.e., in 2005–2010 and 2015–2018). These findings are instructive for forest and urban managers working to achieve multiple Sustainable Development Goals. [ABSTRACT FROM AUTHOR]